Intelligent Optical Systems (IOS) proposes to develop a compact and portable optical fiber biofilm sensor for the in situ detection of biofilms in dental unit water delivery lines. This innovative technique is based on the detection of auto fluorescence due to the presence of the coenzymes NADH and NADPH, tryptophan, and extracellular polysaccharides that are unique signatures of biofilms and their metabolic by-products. In Phase I, fluorescence detection will be used to demonstrate that particular chemical signatures are conclusively indicative of biofilm presence. A pro to type in situ optical fiber biofilm detection system will be demonstrated at the completion of Phase II. The system will be useful in preventing bacterial contamination in dental unit water lines and other fluid delivery systems, especially in medical applications. Biofilm detection can be followed by the release of timely', small, requisite amounts of biocide in order to remove biofilms. By helping to prevent the contamination of dental unit water lines, re-usable catheters, and endoscopes, this compact, portable device will prevent waterborne infections, and prevent the overuse of biocides and their unwanted side effects. PROPOSED COMMERCIAL APPLICATION: Every year, millions of people are infected by waterborne diseases. IOS's compact and affordable in situ sensor will detect bacterially induced biofilms. Timely detection will help prevent many of the diseases that are caused by the presence of biofilm in dental unit water lines and other catheter-like medical fluid delivery systems.